Tour de France: Tearful Richie Porte crashes out with shoulder injury

While he seized the moment to attack the main protagonists in the mountains, his fearless ride is only likely to have extended his stay in yellow for 24 hours, as the Tour continues with another day for the climbers on Wednesday.

Michal Kwiatkowski crashed later, Mikel Landa slammed into the bitumen while trying to take a drink and Michael Valgren, Dylan Groenewegen and Niki Terpstra were also among the many to lose control on an incredibly intense afternoon.

Van Avermaet picked up a one-second bonus overall during an intermediate bonus sprint at 20K from the finish. Froome survived a crash with 45km remaining of the 156.5km stage, just as the riders entered one of the sectors of pavé at Mons-en-Pévèle.

"I'll try to race, but obviously with the cobbles, it's going to hurt", said the 31-year-old.

A slight brush against Alexander Kristoff saw him sit up, but by then Groenewegen had already gone as the LottoNL-Jumbo rider led home Quick-Step Floors' Fernando Gaviria and Peter Sagan of Bora-Hansgrohe.

Richie Porte of BMC Racing, however, has been discharged from hospital after his crash today and the diagnosis is that he has a non-displaced right clavicle fracture.

The man who completed the podium previous year, AG2R La-Mondiale's Romain Bardet, experienced a day in which a succession of mechanical problems - beginning on the very first section of cobbles - left him having to constantly battle back to rejoin the group.

Chris Froome believes the mountains will reveal the true Tour de France contenders as he looks forward to the first of three grueling stages in the Alps.

Tom Dumoulin, meanwhile, suffered a puncture.

John Degenkolb (Trek) won Paris Roubaix back in 2015 but has had to come back from the wilderness and overcome some personal setbacks and serious injury to finally snare another major victory. Degenkolb, severely injured in a training accident in 2016, had to sprint from the front 200m from the line, but held off Van Avermaet for a famous win. "When you hear a doctor say that you know it's no good", he said.

"That was incredibly hard and I have a new level of respect for the guys that ride Paris-Roubaix".

Sunday's stage featured 15 stretches of pavé - the most cobbles in a Tour stage since 1983.

The route starting in Arras contained the highest number of cobblestone sections since the 1980 Tour, with almost 22 kilometers altogether.

"I'm feeling good and optimistic about the upcoming stages", the four-time champion said on Monday, the Tour's first rest day.